Amino acid free stable aluminum/zirconium antiperspirant solution
An amino acid free stable aluminum zirconium polyhydric alcohol aqueous solution having a high anhydrous antiperspirant solid concentration and a high percentage of low molecular weight aluminum species, i.e., containing 60% or more of band IV peak area based on high pressure liquid chromatography, is prepared by adding a zirconium salt to an aqueous polyhydric alcohol solution of a basic aluminum chloride.
1. An amino acid free stable aluminum-zirconium aqueous solution comprising, in percent by anhydrous solid, about 20 to 55% antiperspirant active, about 20 to 75% by weight water and about 1 to 20% by weight polyhydric alcohol having at least 2 carbon atoms and at least two hydroxyl groups and having an aluminum to zirconium atomic ratio of about 0.8 to 10 and a metals to chloride atomic ratio of about 0.8 to 2.1.
2. The solution according to claim 1 , comprising about 35 to 45% anhydrous solid aluminum zirconium antiperspirant active, about 35 to 55% by weight water, and about 10 to 15% by weight polyhydric alcohol and a metals to chloride ratio of about 0.8 to about 1.2 and an aluminum to zirconium ratio from about 2.0 to about 9.0.
3. The solution according to claim 1 , wherein said polyhydric alcohol is propylene glycol.
4. The solution according to claim 2 , wherein said the aluminum zirconium antiperspirant solution has a HPLC Band IV area of about 20 to 75%.
5. The composition according to claim 4 , wherein said the stable solution has a HPLC Band IV area of 45 to 65%.
6. The antiperspirant composition according to claim 2 , wherein the solution has 27 Al NMR spectrum wherein 100% of the total area is contained in the chemical shift of about 0 to about 10 ppm.
7. A dried antiperspirant solution according to claim 1 .
8. The solution of claim 1 in which the polyhydric alcohol has two carbon atoms and two hydroxyl groups.